It is probably a ZK as stated by Dexdog- Has German parts, but a transitional lens to the J-3. Only one way to really find out- and that is to take the optics module out of the focus mount and have a look at the material used. and while you are at it, take of the focus ring and look at the mechanism for the helical. The mechanism for the German LTM Sonnar, very early Russian, and J-3 is much different.
I've recently taken on rebuilding Five "unusual" Sonnars. It's my guess that some are Russian assembled from German parts, and others are Russian copies from the German designs. One is just strange. I've posted two so far, will be putting up three more.
The ZK lenses are reputed to be very good. I had one 1950 J-3 that was just "wrong" optically. The mount was much too long, the focal length was off.